Question

David cuts a cake into two equal halves. He cuts one half into smaller pieces of equal size. Each of these small pieces weighs twenty grams. If he has seven pieces of the cake in total, how heavy is the original cake?

• A. 120 grams
• B. 180 grams
• C. 300 grams
• D. 240 grams

Answer 1

The correct option is D

240 grams

Let the weight of original piece be $x$.
Then the weight of one half is $\frac{x}{2}$.
There are a total of seven pieces. The number of smaller pieces is six which come from the other half.
As each of the smaller piece weighs 20 grams, the weight of one half is 20 x 6 = 120 grams.
Hence the total weight of the cake = 2 $\times$ 120 = 240 grams.